r nested type through an instance ;qualifying expression will not be evaluated

I want to validate email addresses that are entered into a textbox in my program.
 I have a regular expression function to validate ,if the email address is correct then it should read the email address entered in the textbox and send to the  save function  (save logic goes through another function which takes valid email address as input parameter).If email address is invalid it should display en error message :Invalid email address
 Below is the sample code
         Dim Email As String = Me.txtEmail.Text.Trim()
          'Below line throws the access error -here Utility class is another class where all functions are defined.
                If Utilityclass.IsEmailAddressValid(Address) Then
 
        & ...